Hi
What Year group is he, as Orange band could be R, Yr1, Yr2 even Yr3 in some cases, depending on child's ability?
I was a TA for ten years, then a voluntary helper, particularly supporting reading. Younger children feel 'safe' sounding out, and Yes, some will continue to do it even when they know words quite well. In due course they do slip out of the habit.
Does he have a variety of books to read, or only the 'scheme' ones from school? The wider the variety you can offer the better, and not only books - comics, magazines, even 'junk mail', and see what words he can pick out quickly, then see if he can sound out the harder words.
Look for little words within longer words - 'bed' in 'climbed' is a favourite example.
Try to make words, writing and reading a 'fun' activity. If he has particular interests - football, music, nature and animals, other places (geography) - find books, leaflets, travel brochures etc that might engage his interest. Encourage writing with a diary of the day's/weekend's events. Let him write little stories for his favourite toy or teddy. Don't expect perfect spelling, but as long as the initial sound is there, or you can phonically recognise what a word is supposed to be, that will do for a start.
Teachers might not agree with this, but if you read with him a book he enjoys that is way too hard for him, trace the text with your finger as you read, but pause at words you know he can, or should be able, to read then he will have the satisfaction of contributing something to a harder story, even though you are doing the bulk of the work.
Good luck.